Revision 73c632ed block/qcow2.c
| b/block/qcow2.c | ||
|---|---|---|
| 62 | 62 |
|
| 63 | 63 |
#define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */ |
| 64 | 64 |
|
| 65 |
#define MIN_CLUSTER_BITS 9 |
|
| 66 |
#define MAX_CLUSTER_BITS 16 |
|
| 67 |
|
|
| 65 | 68 |
typedef struct QCowHeader {
|
| 66 | 69 |
uint32_t magic; |
| 67 | 70 |
uint32_t version; |
| ... | ... | |
| 300 | 303 |
if (header.magic != QCOW_MAGIC || header.version != QCOW_VERSION) |
| 301 | 304 |
goto fail; |
| 302 | 305 |
if (header.size <= 1 || |
| 303 |
header.cluster_bits < 9 ||
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|
| 304 |
header.cluster_bits > 16)
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|
| 306 |
header.cluster_bits < MIN_CLUSTER_BITS ||
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|
| 307 |
header.cluster_bits > MAX_CLUSTER_BITS)
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|
| 305 | 308 |
goto fail; |
| 306 | 309 |
if (header.crypt_method > QCOW_CRYPT_AES) |
| 307 | 310 |
goto fail; |
| ... | ... | |
| 1583 | 1586 |
} |
| 1584 | 1587 |
} |
| 1585 | 1588 |
|
| 1589 |
static int get_bits_from_size(size_t size) |
|
| 1590 |
{
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|
| 1591 |
int res = 0; |
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| 1592 |
|
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| 1593 |
if (size == 0) {
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| 1594 |
return -1; |
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| 1595 |
} |
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| 1596 |
|
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| 1597 |
while (size != 1) {
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|
| 1598 |
/* Not a power of two */ |
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| 1599 |
if (size & 1) {
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|
| 1600 |
return -1; |
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| 1601 |
} |
|
| 1602 |
|
|
| 1603 |
size >>= 1; |
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| 1604 |
res++; |
|
| 1605 |
} |
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| 1606 |
|
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| 1607 |
return res; |
|
| 1608 |
} |
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| 1609 |
|
|
| 1586 | 1610 |
static int qcow_create2(const char *filename, int64_t total_size, |
| 1587 | 1611 |
const char *backing_file, const char *backing_format, |
| 1588 |
int flags) |
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| 1612 |
int flags, size_t cluster_size)
|
|
| 1589 | 1613 |
{
|
| 1590 | 1614 |
|
| 1591 | 1615 |
int fd, header_size, backing_filename_len, l1_size, i, shift, l2_bits; |
| ... | ... | |
| 1619 | 1643 |
header.backing_file_size = cpu_to_be32(backing_filename_len); |
| 1620 | 1644 |
header_size += backing_filename_len; |
| 1621 | 1645 |
} |
| 1622 |
s->cluster_bits = 12; /* 4 KB clusters */ |
|
| 1646 |
|
|
| 1647 |
/* Cluster size */ |
|
| 1648 |
s->cluster_bits = get_bits_from_size(cluster_size); |
|
| 1649 |
if (s->cluster_bits < MIN_CLUSTER_BITS || |
|
| 1650 |
s->cluster_bits > MAX_CLUSTER_BITS) |
|
| 1651 |
{
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|
| 1652 |
fprintf(stderr, "Cluster size must be a power of two between " |
|
| 1653 |
"%d and %dk\n", |
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| 1654 |
1 << MIN_CLUSTER_BITS, |
|
| 1655 |
1 << (MAX_CLUSTER_BITS - 10)); |
|
| 1656 |
return -EINVAL; |
|
| 1657 |
} |
|
| 1623 | 1658 |
s->cluster_size = 1 << s->cluster_bits; |
| 1659 |
|
|
| 1624 | 1660 |
header.cluster_bits = cpu_to_be32(s->cluster_bits); |
| 1625 | 1661 |
header_size = (header_size + 7) & ~7; |
| 1626 | 1662 |
if (flags & BLOCK_FLAG_ENCRYPT) {
|
| ... | ... | |
| 1702 | 1738 |
const char *backing_fmt = NULL; |
| 1703 | 1739 |
uint64_t sectors = 0; |
| 1704 | 1740 |
int flags = 0; |
| 1741 |
size_t cluster_size = 4096; |
|
| 1705 | 1742 |
|
| 1706 | 1743 |
/* Read out options */ |
| 1707 | 1744 |
while (options && options->name) {
|
| ... | ... | |
| 1713 | 1750 |
backing_fmt = options->value.s; |
| 1714 | 1751 |
} else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) {
|
| 1715 | 1752 |
flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0; |
| 1753 |
} else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) {
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|
| 1754 |
if (options->value.n) {
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|
| 1755 |
cluster_size = options->value.n; |
|
| 1756 |
} |
|
| 1716 | 1757 |
} |
| 1717 | 1758 |
options++; |
| 1718 | 1759 |
} |
| 1719 | 1760 |
|
| 1720 |
return qcow_create2(filename, sectors, backing_file, backing_fmt, flags); |
|
| 1761 |
return qcow_create2(filename, sectors, backing_file, backing_fmt, flags, |
|
| 1762 |
cluster_size); |
|
| 1721 | 1763 |
} |
| 1722 | 1764 |
|
| 1723 | 1765 |
static int qcow_make_empty(BlockDriverState *bs) |
| ... | ... | |
| 2920 | 2962 |
{ BLOCK_OPT_BACKING_FILE, OPT_STRING },
|
| 2921 | 2963 |
{ BLOCK_OPT_BACKING_FMT, OPT_STRING },
|
| 2922 | 2964 |
{ BLOCK_OPT_ENCRYPT, OPT_FLAG },
|
| 2965 |
{ BLOCK_OPT_CLUSTER_SIZE, OPT_SIZE },
|
|
| 2923 | 2966 |
{ NULL }
|
| 2924 | 2967 |
}; |
| 2925 | 2968 |
|
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